Caption: Aorta surgery. Open chest cavity during surgery to repair an aneurysm of the aortic arch. The metal ring (centre right) is a previously-implanted aortic valve, beyond which lies the heart. The aorta (the main artery from the heart) normally arches up from this valve, but in this patient the arch developed an abnormal swelling (aneurysm). Blood has been rerouted from this area, allowing the surgery which has here removed most of the abnormal tissue. An artificial aortic arch will be implanted to replace it. The surgical instruments include a suction tube (red), the metal chest retractors, and a stitching needle (upper left). For images of the surgery, see M551/331-336.